Problem: Evaluate the following expression when $y = 4$ and $x = 6$. $6$ $y$ $^2 + 3$ $x$ $ + 9$
Answer: Substitute $4$ for ${y}$ and $6$ for ${x}$ $ = 6{(4)}^2 + 3{(6)} + 9 $ Remember order of operations. Evaluate the exponent before you multiply. $ = 6(16) + 3{(6)} + 9 $ $ = 96 + 18 + 9 $ $ = 123$